The Phase 1/2 Intergroup study E4412 (NCT01896999; ClinicalTrials.gov) investigated checkpoint blockade with nivolumab (Nivo) and ipilimumab (Ipi) in relapsed/refractory (R/R) classic Hodgkin lymphoma (HL) while concurrently targeting CD30+ Hodgkin Reed Sternberg cells with the antibody-drug conjugate brentuximab vedotin (BV). 147 patients ≥12 years were randomized between BV/Nivo and BV/Ipi/Nivo; 132 patients are included in primary efficacy analysis. The primary endpoint, complete response (CR) rate, was 64.7% (52.2, 75.9) for BV/Nivo and 70.3% (57.6, 81.1) for BV/Ipi/Nivo (one-sided p=0.29). The median survival follow-up is 38.0 months (interquartile range 32.6-48.1). Progression-free survival (PFS) did not significantly differ between the two arms (HR=0.78, CI 0.39-1.57, one-sided p=0.24). Treatment-related grade 3+ toxicities in the adult cohort, excluding rash, was similar between both arms (38.5% BV/Nivo and 39.3% BV/Ipi/Nivo); there was higher frequency of grade 3 rash with BV/Ipi/Nivo (24.6%) compared to BV/Nivo (9.2%). We compared PFS by stem cell transplantation (SCT) status in a planned post-hoc comparison; 58 patients received SCT; 36-month PFS (from SCT) was greater than 90% for both arms. Sixty-six patients were alive and progression free after the first scan (disease evaluation) and did not undergo SCT. The 36-month PFS (from first scan) was 73.0% (54.5, 85.0) for BV/Ipi/Nivo compared to 45.8% (26.3, 63.4) for BV/Nivo (HR=0.45, CI 0.19-1.08, one-sided p=0.03). The study did not meet its primary endpoint of superior CR rate for the triplet, but it supports the use of checkpoint-ADC induction prior to auto SCT, and there is an intriguing signal of disease control for patients wishing to defer or avoid SCT for the triplet of BV/Ipi/Nivo.
Diefenbach et al. (Mon,) studied this question.